Hit game This War of Mine gets massive discount on both Android and iOS
It's a well put-together masterpiece of survival / base management / visual storytelling and has been lauded by both players and critics. The game will usually set you back about $10 or $15, but has now been significantly discounted — it costs $1.99 on the App Store and $2.99 on the Play Store.
If you haven't gotten a chance to play it yet, maybe now is a great time to check it out! It also has an expansion with extra levels, which will set you back another $2.59.